Colloidal mordant bath and process of making it



Patented Apr. 23, 1929.

1mm. aa'xatonn OF, STATE eoLLneE," mammalian I No Drawing.

This invention relates to the dyeing of cotton, silk, wool, and othermaterials, and to the weighting of silk and the like, and it has as anobject to simplify the process of, and to shorten the time required for,bringing the dyed material to the final color or shade de sired.

Although the invention is not limited to employment of any particularform of dye and the process of its use, reference is made to Turkey-reddyeing as an example of the time required, and the meticulous care thathas to be exercised, in the carrying on of dyeing operations asheretofore performed. 7

In brief, the process of Turkey-red dyeing as commonly practiced may besummarized as follows: (1) the fiber is bleached; (2) some soap-formingoil is adsorbed on the fiber; (3) the oil is saponified on the fiber;

(4) the excess soap and oil are removed from the fiber (5) thesoap-containing fiber ad- ,sorbs, alumina (6) the alumina adsorbs cal-.cium alizarate (7 theclearing 0perationremoves dirt, increases the sizeof the calcium ahzarate particles, and varnishes the. dyed V fiber witha very thin film of tin soap, where- I by the brilliancy and fastness ofthe-dye are,

wincreased.

In Turkey-red v(lyeing as commonlyipracthe fiber; the, relation of: the,metallic mordant to the fixing agent; the relation of the dye to themetallic mordant, and the brightening operation. Furthermore, the

fixing of the metallic mordant on the fiber is the most clumsy,unscientific, and lengthy- Sincealumina-adsorbs soap from soap solu-itions, and soap with aluminum salt solutions forms a colloidal complexof alumina and fatty acid, the problem of simplifying, and of'shorteningthe time required for the dyeing of fiber-and other materials resolvesitself into the preparation of, and the invention accordingly providesfor a colloidal'solution of aluminum. or other suitable metalhe salt anda fixing agent suchas soap, soap forming materials, tannin, sulphonatedoils, or their equivalents, and then fixing such a coLLoInA monnnn'rBATH Ann rnocnssj or" ma as fir.

Application filed December 14, 1927. Serial No. 240,078.

,ticed, there are four factors to consider; namcly-ztgTherelation of thefixing agent to sium iodide solution, thesilver-ioedid viodide solution,for "example 20.5 c-

'sorpt-ion' of the excess" iodid colloid solutions are milky an colloid,on the fiber, g suitable stabilizing.

agent, such, for example, as gelatineand glues, casein, gum arabic,etc., maybe added, if desired. The prior art shows, in the steps,pertaining to dyeing, the precipitation of metallie fio salts from truesolutions onto thefiber'ybut this invention is characterized by theemployment, in a single bath, of a colloid solution of a metallicmordant and a fixing agent, in the fixing of the mordant in colloid formon the material. Colloidal particles are the best adsorbents for dyes. r

A true solution is one in which the solute is dispersed in the solventin molecular or ionic condition; for example, sodiumchlo ride dissolvedin water, where there-are some sodium ions, some chlorineionsfand someundissociated sodium cl1loride;f;f ,The particles are too small to beseenflwith the naked eye or with a powerful miscroscope '75 with anysort of illumination. i

In colloidalsolutions, the particles aie'inot molecular orionic; forexample,'silver, iodide as prepared from 0.05 normalsolut 1" silvernitrate and potassium iodide. f ne adds from a 'burette'; whilestirring, 20""c'c. of silver nitrate solution -to an equivalenta'mountof 20 cc; of potassium 'iodide 'solfution, the preeipitatedsilveriodide coagulafes and settles out. This is not a stable colloid s5solution." If to another beaker containing a slight excess of silvernitrate solution, "for example 20.5 00., one adds 20 cc.-of-*p'otasremains in suspension as a p'ositi'v tolldidf eo having beenstabilized by'theadsorptioiibf the excess of silver ions." This is 'acolloidal solution of silver iodide; Furthermorm fif one adds slowly andWith stirring 20icciof silver nitrate to a slight excess ofpotasfsiurln' efi loidal suspension of silver iodide that has a negativecharge, 'du' toth'e escence strongly. v t, In other words, colloidsoluti in which the dispersed media as many molecules bound t'ogetheparticle possesses an electricafch'a' 1 present d the s f'S :ilar to anion,but it hasnot theproperties of an ion ormoleculei Tlicol'loi'dalparticle is correspondinglylarger than the molecule or ion.The individual" articlefeannot' be seen with the naked eye, It? can'beobserved im -tussah silk, wild s1 only with a microscope by dark fieldillumination, and it shows Brownian movement. Such solutions exhibitstrongly opalescence; they do not settle, and they cannot be filteredout by filter-papers, but they may be filtered with ultra filters. 7

Therefore the mordant bath of this invention, being a colloidalsolution, is milkyand exhibits opalescence strongly. The mordant elementthereof is adsorbed strongly by the fiber or other material to bemordanted, and when freshly applied it cannot be washed by Tnpre waterfrom the mordanted material.

e proportions and concentrations of the ingredients may be variedthrough any range where a suitable colloid solution is formed, as wellas the kind of salts, the kind of dye used to produce the desired color,and the temperatures at which the mordant is applied and fixed.

The metallic salts of the weakly dissociated acids, such as acetates,tartrates, citrates, lactates, etc., form the most suitable colloids,and they may be used advantageously and they are taken up readily by thematerial being treated, but. they are not the only ones that may beemployed satisfactorily.

The mordant may be applied by dipping the material (which may be wetordry, but

y allowing the material to stand for a time in the bath, or by spraying,or by any other suitable method. The mordant may be fixed by heating inan air or gas filled oven, or in hot water, or in any suitable hot orcold solution. The mordant may be applied at room temperature or at anyother suitable temperature. The loosely-held excess mordant may beremoved by washing in water or other suitable medium before the mordantis fixed on the material by heat.

The mordant may be used before the dyeing operation for taking the dye;or it may be applied after the dyeing operation, in order to bri htenthe color of the dyed material, and t e better to fix the dye on thematerial, and to protect the dye from bleeding and the action of gases,washing preparations, and other chemicals.

The mordant made in accordance with this invention from suitablemetallic salts or mixture of metallic salts maybe used for the weightingor loading of silk, waterproofing fa 'ric, or in the tanning of hidesand skins. It leaves the material soft and flexible and dyed a more evenand uniform color, and it does not leave within the material chemicalsthat would cause its deterioration.

The metallic mordant and fixing agent in a colloidal solution may beapplied in one bath to cotton, mercerized cotton, kapok,

linen, hemp, ramiehjiute, wool, mohair, silk, rayon,'leather, hides,

preferably wet) into the mordant bath, or

more lustrous color is obtained. It is best fixed by hot liquids orsolutions; hot water is excellent.

Following is an example of one way of preparing and using a mordantbath, in accordance with this invention, in a short process of dyeingTurkey-red:

An aluminum soap colloid mordant bath isprepared from aluminum acetateand sodium oleate, as by adding in the proportions of 25 cc. of a tenthnormal aqueous solution of sodium oleate very slowly to 100 cc. of atwo-tenths normal solution of aluminum actate while stirring themixture.

As shown, for example, in the case of silver iodide, the most stablecolloidal solutions are formed when the fixing agents, such as soap,soap-forming materials, tannins, sulphonated oils, or their equivalents,are not present in equivalent quantities; and, moreover, it is better toadd slowly the ingredient of lesser concentration to the one with thegreater concentration, meanwhile stirring well the mixture.

In order further to explain: Suppose one has solutions of sodium oleateand aluminum acetate, each one-tenth normal, equal quantities of thesesodium oleate and aluminum acetate solutions do not form a very stablecolloidal solution; but a stable colloidal solution results, if, forexample, 25 cc. of the sodium oleate solution be added very slowly to200 cc. of the aluminum acetate solution while being well stirred, or astable colloidal solution is formed, if, for example, 25 cc. of thealuminum acetate solution be added slowly to 200 cc. of the sodiumoleate solution while being well stirred. I do'not restrict myself tothe exact proportions given in the foregoing examples or to the. exactmethod of preparing the colloidal solution set forth.

The material to be treated is soaked in water and dipped into themordant bath, rinsed in pure water, and dipped into boiling water; andthe process is repeated until the ggsired amount of mordant is fixedonthe er. The material then is ready for the dye without furthertreatment, it may be dyed with alizarin G in the presence of calciumacetate, and-it may be brightened by again mordanting in the mordantbath, and steamed. A beautiful Turkey-red color results that is just asbright, and as fast to light, washing, and so on, as any produced by theold-time method.

No strong clearing solution is needed to brighten this color, as thereis no excess of oil to remove, and there is practically no way for thematerial to accumulate dirt during the two operations. Consequently, thegoods may be steamed or boiled with water until the particles of calciumalizarate have increased to such a size as to produce a brighter redcolor.

In the weightingor loading of silk in accordance with this invention,any suitable metallic salt and any suitable soluble soap or itsequivalent may be used; for example, the following, in proportionsstated: 25 cc. of a tenth normal aqueous solution of sodium oleate isadded to 100 cc. of a two-tenths normal aqueous solution of stannous orstannic acetate, and thus forming a colloidal bath. The silk is washedin Water, dipped into the bath, rinsed in pure water, and dipped intoboiling water; and the process repeated until the desired amount ofmordant is fixed to the fiber. The silk now is Weighted and ready fordyeing Without further treatment.

What I claim as new, and desire to secure by Letters Patent, is-

1. A mordant bath comprising a colloidal solution of metallic salt and afixing agent.

2. A mordant bath comprising a-colloidal solution of metallic salt and afixing agent, and a stabilizing agent.

3. A mordant bath comprising a colloidal solution of metallic acetateand a fixing agent.

4. A mordant bath comprising a colloidal solution of metallic acetateand a fixing agent, and a stabilizing agent.

5. A mordant bath comprising a colloidal solution of metallic salt andoleate.

6. A mordant bath comprising a colloidal solution of metallic salt ofweakly dissociated acid and a fixing agent.

7. A mordant bath comprising a colloidal solution of metallic salt ofweakly dissociated acid and an oleate.

8. A mordant bath comprising a colloidal solution of metallic acetateand oleate.

9. A mordant bath comprising a strongly opalescent colloidal solution ofaluminum acetate and an oleate.

10. A soap colloid mordant bath comprising in colloidal solutionmetallic salt'and sodium oleate.

11. A soap colloid mordant bath comprising in colloidal solutionmetallic salt of weakly dissociated acid and sodium oleate.

12. A soap colloid mordant bath comprising in colloidal solutionmetallic acetate and sodium oleate.

13. A soap colloid mordant bath comprising in colloidal solutionaluminum acetate and sodium oleate.

1 1. A mordant bath comprising a colloidal solution of mixture ofmetallic salts and a fixing agent.

15. The process of making a stable colloid mordant bath that comprisesthe taking of solutions of metallic salt and a fixing agent of differentconcentrations, and adding the solution of lesser concentration to thesolution of greater concentration while agitatmg.

16. The process of making a stable colloid mordant bath that comprisesthe taking of solutions of metallic salt and a fixing agent of differentconcentrations, and adding a lesser amount of the solution of lesserconcentration to a greater amount of the solution of greaterconcentration While agitating.

17. The process of making a stable colloid mordant bath that comprisesthe taking of solutions of metallic acetate and oleate of diiferentconcentrations, and adding the solution of lesser concentration to thesolution of greater concentration While agitatin LYTLE RAYMOND PARKS.

(T In testimony whereof I afiix my signature.

